An estimate of the Senate immigration reform bill by the nonpartisan Congressional Budget Office shows that the proposal won't blow a hole in the federal budget. In fact, it's actually projected to significantly decrease federal budget deficits between 2014 and 2023.

That's a big positive for the bill's supporters as the Senate attempts to pass the ambitious plan before the Fourth of July holiday.

"This report is a huge momentum boost for immigration reform," Sen. Chuck Schumer (D-N.Y.), one of the bill's authors, said in a statement.

Here are the details of the report, and why they matter:

1. How Much It Costs

The budget office estimates that the bill will result in a net savings of $175 billion over a decade for the federal government, with the costs of implementation factored in. New income and payroll taxes would offset federal spending on things like Medicaid benefits, subsidies granted under President Obama's healthcare law, and tax credits.

In the second decade after the law is put into place, it is projected to decrease federal deficits by $700 billion. To put those numbers into perspective, the federal government is projected to run a $642 billion deficit this year.

Those data points will be used by supporters of the bill to try and win over -- or shoot down -- GOP budget hawks who are skeptical about the proposal.

"The CBO has further confirmed what most conservative economists have found: reforming our immigration system is a net benefit for our economy, American workers and taxpayers," added Sen. Marco Rubio (R-Fla.), another author the bill.

2. How Many People Will Come to the U.S.

Overall, the budget office projects that the immigration bill would add 10.4 million new residents to the country over 10 years, compared with the number who would come in under current law. Most of those people would be legal permanent residents. About 1.6 million would be temporary workers and their dependents.

The CBO found that 8 million undocumented immigrants would legalize through the legislation. But those are people who are already living in the U.S., so they don't count in the tally of new immigrants.

Looking at the impact of the legislation over 20 years, the office found the U.S. population would see a net increase of 16 million people.

The office also said that some aspects of the legislation would make it harder for people to come to the U.S. illegally, but that others -- like new temporary worker programs -- could lead to new ways for immigrants to enter the U.S. illegally.

Overall, however, the Senate legislation would cut the annual flow of undocumented immigrants into the country by 25 percent, according to the estimate.

3. The Cost of Healthcare

Republicans have expressed worries over the cost of healthcare that new immigrants would receive under the immigration bill. But the CBO estimate shows that those costs would be far outshadowed by the economic gains immigrants would make over the next decade.

The federal government would spend $262 billion during the 10-year period outlined in the estimate for things like Medicaid, government-subsidized insurance and tax credits for new immigrants. But increased federal revenues for income and payroll taxes would offset those losses. And the greater economic gains expected under the legislation would far outweigh the costs, produced the net budget decreases we mentioned above.